Risk Factors Of AKI In Valve Reoperation Patients And The Efficacy Of CRRT In AKI

Objectives:Post-operative AKI is a challenging complication in cardiac surgery patients.However,the risk factors of AKI and the effective AKI management strategies are largely unknown.In this study,we aimed to identify the risk factors of acute kidney injury(AKI)after valve reoperation and to investigate the efficiency of continuous renal replacement therapy(CRRT)on AKI patients after cardiac surgery.Methods:The study was composed of two parts.Part I.Retrospective analysis of the risk factors of postoperative AKI in valve reoperation patients.From December 2007 to October 2014,we collected 272 patients who received valve reoperation from the database of Cardiovascular Institute,Xinqiao Hospital,Army Military Medical University.Of these patients,12 patients were diagnosed with AKI after cardiac surgery.The gender,age,weight,preoperative conditions,operation and intraoperative information,cardiac multifunctional color Doppler ultrasonography,liver function,postoperative ventilator support time,postoperative ICU stay time and other information were collected both in AKI group(n = 12)and non-AKI group(n = 260).The difference was compared with non-pair t test,and the risk factor of AKI was analyzed by Logistic regression analysis.Part II.To analyze the efficiency of CRRT in AKI.18 patients diagnosed as AKI who needed CRRT after cardiac surgery were divided into two groups: effective group A and ineffective group B,hereinafter referred to as group A and group B.The clinical information before and after CRRT was recorded.Also,the effect of renal function on patients’ prognosis was analyzed.Results:Part IThe incidence of AKI was 4.41% in these re-do valve replacement patients,4 patients died post-operation.The mortality rate in these AKI patients was 33.3%,which was significantly higher than that of non-AKI group,which was 0.38%.Multivariate Logistic regression showed that the preoperative non-heart diseases(OR = 9.104,p = 0.029)(OR = 90.998 p = 0.000),emergency surgical aortic clamping time over 120 min(OR = 46.449 p = 0.016),preoperative left ventricular diameter greater than 60 mm(OR = 0.114 p = 0.041)were independent risk factors of AKI in valve reoperation patients.Part II18 cases of AKI patients were treated with CRRT,which was effective in 11 patients(group A),ineffective in 7 patients(group B).There was no significant difference in age,operation time,CRRT duration,postoperative CRRT time and hospitalization time between these two groups(p > 0.05).There was a significant difference in gender distribution between the two groups(p < 0.05).There were significant differences in heart arrhythmia and cardiac function scores between groups A and B(p < 0.05).The proportion of heart rate disorder(75.0%)in group B was higher than that in group A(0.00%).After CRRT,serum BUN,SCr,K +,PLT,CVP and Lac were decreased(p < 0.05),and other indexes were not changed(p > 0.05).Importantly,serum K +,Na +,HR,CVP and Lac in group A were lower than those in group B(p < 0.05),SBP and DBP in group A were higher than those in group B(p < 0.05).Conclusions:1.AKI is one of the most dangerous complications in valve reoperation patients.Preoperative treatment of patients with other systemic diseases,choose a reasonable timing of surgery,shorting the cardiopulmonary bypass time,strengthen the monitoring of renal function changes in patients could reduce the incidence of AKI.2.CRRT is an effective treatment for postoperative AKI,CRRT can correct water and electrolyte disorders,improve heart and lung function,improve the treatment efficacy.